<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
     *{
         padding: 0px;
         margin: 0px;
     }

    .out{
        width: 500px;
        height: 500px;
         /* border:1px red solid;  */
        outline: 1px red solid;
        margin: 0px auto;
        /* padding-top: 50px; */
    }
    .inner{
       width: 200px;
       height: 200px;
       /* border:1px solid blue;  */
       outline: 1px blue solid;
       margin: 5px auto;
    }
     
  

    </style>
</head>
<body>
 
          <div class='out'>
              <div class='inner'></div>
          </div>
    
</body>
</html>